Thursday, August 25, 2011

Eat The New Thing!

Being a die-hard dogged rationalist means that just about everything that human beings do gets on your nerves. It also means that someone is always trying to convince you that their way of thinking is more correct than whatever else other people do.  Diet is an easy target for this sort of warring because practically nobody has a proper diet, and because the ideas of what constitutes "proper" is very poorly understood, so it is easy to find new ideas and new thinking that supplants the old.

I get all sorts of things about diet fads and how this is the thing you should eat.  It's very easy to be fooled by it as well, because often times, there are real studies to back some of what people say about various foods...  the problem is that there isn't much understanding of those studies or even the scientific significance of their results by the people who spin fads out of them.  There are, for instance, studies that show that acai berry is a rich source of antioxidants...  so it becomes the new miracle food.  Problem is it ignores the fact that a berry which is rich in antioxidants is about as rare as a liquid that happens to be wet.

So I feel I have to rip apart at least one of the more current food fads that I keep getting requests and spam about -- that being, the raw food movement.  I don't think I have any limits to how far I can take this rant, but then, the same can be said about a lot of things.  Well, here goes...

The raw food movement is based entirely on partial truths and very limited understandings of food value.

It takes an idea, which is, at its base, not all that bad...  that is...  increased consumption of fresh fruits and vegetables, and takes it to an extreme that it is the only type of food one should ever eat.  There's not a whole lot about it which is not based on bad logic and horrible extrapolations of things which are only small parts of the truth rather than the whole picture.

Anytime someone claims to have the "correct" path, it's often the case that the position they take is very extreme.  It seems to be a basic human failing that people who exercise certain seriousness towards goals lack any sort of concept of a middle ground.  The raw food movement falls clearly in this vein, as a straight out extreme position which is emphatically stupid on several levels.

The only part of the position they take which has some element of truth is the assertion that nutrients are lost during cooking.  This is true for certain nutrients in certain cases, but it is not a universal truth.  Some substances are lost due to the heat exposure, and some are actually increased in their availability.  Even more confusing still is that the same substance from two different sources may yield different results based on cooking vs. not.  In the case of tomatoes or spinach, at least 75% of the available vitamin C is lost during cooking.  In the case of broccoli, however, cooking reduces the vitamin C content by only about 20%.  In the case of tomatoes, vitamin A also sees a small loss due to cooking, but both broccoli and spinach see a fair increase in available vitamin A.  In fact, spinach is a classic example of something which is pretty useless on a nutritional level when taken raw.

In general, raw food diets are deficient in minerals like iron, calcium, magnesium, and also deficient in a few types of B vitamins and in vitamin D.  Soluble fiber is also significantly lower, because cooking can actually solubilize otherwise unavailable fiber.  People do lose weight when switching to raw food diets, but that is typically related to a few factors.  One is that raw food means a lot of the bulk and water content is still present, which means that you ultimately eat a lot less food and fewer total calories for a given amount of food volume.  Cooking tends to release and cook off a lot of this excess water and reduce the overall volume, so you end up consuming more actual food per unit volume.  The other, more significant factor, of course, is the fact that diet changes bring about results simply because of the shift compared to what a person was eating prior to that point.  Someone who was already eating a very healthy diet prior to going raw won't see that much improvement in their weight compared to someone who was eating fast food burgers as a staple food.  This is generally not a bad thing if you're overweight and are looking to lose weight.  But if you fall into that group, it is very likely that your intake of raw fruits and vegetables was poor to begin with.

I do hear the common argument that the enzymes are important and valuable.  Yes, indeed, raw fruits and vegetables do have a higher enzyme content, and that is about the only part of this assertion which is true.  Any notion that the enzymes are valuable and/or important to our health is completely false.  There are pretty nearly zero enzymes that make it past the stomach, except as their constituent amino acids.  Those few that have been shown to get beyond the gut barrier are also shown to either never be absorbed, or are entirely useless to us.  In reality, all the enzymes we do need are ones our bodies make so long as all the necessary components are available.  There is zero clinical evidence to support that there is any enzyme in any food whatsoever which is nutritionally significant.  There are a few which exist in food which are identical to proteins our body uses, but in reality, we don't absorb them whole -- we absorb their component aminos and recreate the proteins once again.  Occasionally, there are a few which help in digestion of things most people normally can't digest, but the value of these things are transient at best, and effectively nonexistent after the time you swallow your food.  In short, supporting your body processes and getting the enzymes you do need means we need to get a sufficient amount of protein in our diet.  What do you know?  Something that is also made more available by cooking.

Yes, you can overcome some of the issues of nutrient deficiency if you adjust your preferences and/or supplement heavily.  Soy, for instance, is definitely full of complete protein, but it is also heavy in estrogens and sodium.  Nori seaweed can offset the B12 shortage that is inherent in any raw food diet (excluding one that includes raw meat, which has its own issues), but nori also contains a great deal of iodine.  Never mind the fact that a lot of legumes are flat out dangerous to eat at all if uncooked.  Raw kidney or fava beans, for instance, contain hemagglutinins which can cause red and white blood cells to clump.  Toxicity can be experienced in as few as 5 beans.  But cooking can render these nonexistent.  It's also why you can never find raw beans in a can.  It's simply not safe for people to consume.

Also, I think people forget that we do process foods in order to make them safer.  Uncooked food carries with it the risk of contamination.  This is obviously something we worry a great deal about when it comes to raw meat, but not so much when it comes to raw vegetables.  It's also worth noting that if you're an organic food fan in addition to raw, you actually put yourself at greater risk in this regard because the allowable fertilizers and pesticides according to organic regulations are more likely to carry pathogens.  However, it is still a very small risk even with that in mind, to be fair.  Yes, there are risks associated with some forms of cooking, especially at very high temperature, but these are not all too statistically significant as one might think, unless you are dealing with food that can be qualified as at least partially burnt.  I think most people, regardless of the dietary habits, do have an aversion to burnt food.  Yes, there are times when people like things like char-grilled sausages, and it does contain trace amounts of carcinogens, but in an otherwise controlled diet, you can offset most any risk of this.  Moreover, inclusion of things like beer or wine at the time of consumption can also essentially wipe out this risk.

About the only unique benefit of a raw diet is the serious reduction in sodium, and hypotensive effect thereof.  Unfortunately, I can't find any strong research to support this, though there are some short term studies that seem to suggest this.  Now I say that this is about the only unique benefit because most other effects can be associated with simply including a sufficient degree of fruits and vegetables in your diet and having a relatively decent percentage of that be raw.  In other words, things like increased fiber and antioxidants, decreased heart disease, weight reduction, cholesterol reduction, etc...  cannot be connected specifically to the *raw* aspect of the diet.  Short term weight reduction, maybe higher for a raw vegan diet, due to the aforementioned low-calorie effect of going raw.  However, I don't think you can make the same argument over the longer term, and there are potential malnutrition risks unless you supplement or take extreme and not-so-sustainable shifts in your food choices.

Knowing the average raw food fanatic, I would expect a variety of angry screaming, and defensive posturing about how there are sources to refute me.  What I have to laugh at is the fact that fanatics can only find sources within their own circle of fanatics.  Medical facts do not work that way.  As I've said before in my vegetarianism post some months back, all indications are that well-balanced diet is the best.  Taking an extreme view on food is the exact opposite of that.  Activism will only get you swept away on an ocean of lies even if there are a handful of half-truths mixed in.  Just remember the simple mnemonic for the word "diet" -- Do I Eat Thoughtfully?  Chances are that if you can describe your diet in terms of a "popular movement", the short answer is NO.